The invention relates, in general, to an apparatus and method for forming an occlusion in a mammalian body, and, in particular to an apparatus and method for internally inducing a magnetic field in an aneurysm to embolize the aneurysm with a magnetically-controllable substance.
Like all parts of the body, the brain is composed of living cells that require a blood supply to provide oxygen and nutrients. A hemorrhage in a blood vessel in the brain or in the space closely surrounding the brain is a common cause of strokes. Hemorrhage refers to bleeding into the brain, usually because of a problem with a blood vessel. The problem is often an aneurysm.
An aneurysm is an abnormal bulging outward of blood vessel wall. The wall may smoothly bulge outward in all directions (a fusiform aneurysm) or it may form a sack arising from one wall (a saccular aneurysm). If the aneurysm ruptures, a hemorrhage occurs. This can compress and irritate the surrounding blood vessels, resulting in a reduced supply of oxygen and nutrients to the cells, possibly causing a stroke.
Aneurysms can be treated from outside the blood vessel using surgical techniques or from inside the blood vessel using endovascular techniques. Endovascular treatment of an aneurysm is performed using a catheter. X-ray, magnetic resonance imaging (MRI) equipment, or other visualization equipment may be used to view the progress during the procedure.
A magnetically directable embolic such as an acrylic, iron-containing glue has been proposed to fill or obliterate aneurysms. The embolic is delivered by means of a catheter and is directed into an aneurysm with an external magnetic field generated by a permanent magnet or electrogmanetic device used for Stereotaxis prcedures such as a prototype device made by Stereotaxis Inc. of St. Louis, Mo. An example of such a device is shown and described in U.S. Pat. No. 6,014,580 to Blume, et al. Problems with this approach include that the Stereotaxis machine is cumbersome and expensive and, in some cases, the external magnetic field produced by the Stereotaxis machine is not strong enough to control delivery of the iron-containing, magnetically-directable glue into the aneurysm.
An aspect of the present invention involves a magnetic detachable embolization apparatus for embolizing an aneurysm of a blood vessel. The apparatus includes an element adapted to be detachably connected to a distal portion of a catheter for insertion within an aneurysm of a blood vessel, the element being shaped to be retained within the aneurysm, and one or more magnets carried by the element to internally induce a magnetic field from within the aneurysm to control a magnetic field controllable embolic to embolize the aneurysm. The one or more magnets may be one or more permanent magnets or electromagnets.
An additional aspect of the present invention involves a method for embolizing an aneurysm of a blood vessel. The method includes providing a magnetic-field controllable embolic at an aneurysm in a blood vessel, and internally inducing a magnetic field at the aneurysm site to control the magnetic-field controllable embolic to embolize the aneurysm.
Other features and advantages of the invention will be evident from reading the following detailed description, which is intended to illustrate, but not limit, the invention.